The goal of a dental implant system is to restore the patient to normal function, comfort, aesthetic, speech and health regardless of the current oral condition. These implant systems are based on the implantation of dental implants, such as dental implants made of biocompatible titanium, through insertion into the patient's jawbone. In this respect, the use of biocompatible titanium started in Sweden as early as 1950, and has since then been further developed and spread world-wide. During the 1980's a number of implant systems entered the world market. Methods are known in the art to attach a dental superstructure to an implant. A couple of methods are based on the use of a screw member. Theses screw members can attach the superstructure to the implant, either directly or via spacers.
When implants are implanted in the mouth of a patient who has been without teeth for some time problems arise due to degeneration of bone. If a person has been without teeth for some time, the jawbone that is not under strain of natural teeth or implants, will dissolve and assimilate over time, yielding less bone material for the proper anchoring of a dental implant. To find enough bone for optimal implantation, the implant has to be angled so that the general axis of the implant projects out of the mouth. Fixing a superstructure with a screw member in a straight screw channel to such implants necessitates that the mouth of the screw channel may be forced to be placed on a visual surface of the dental superstructure. Also, the optimum placement of the implant, due to the present dental situation, often results in a non-optimum placement of the dental superstructure in terms of the patient's aesthetics, phonetics and bite.
Therefore, there is a need in the dental field for greater freedom of placement of a dental implant in order to optimize the stability and success of the implantation, while still achieving good aesthetics, phonetics and bite of the patient.
Furthermore, in the above mentioned dental situation there is a need to be able to use an implant placed optimally with regard to the dental situation, that is, the anatomy of the jawbone, while still allowing the dental superstructure to be applied in an optimal way to said implant, such that the mouth of a screw channel not is visible from outside the mouth of the patient.
The means already known in the art for achieving this goal include the use of angled spacers and dental superstructures attached to the implant with adhesive or with other techniques not based on the use of a screw member. The angled spacers have many drawbacks and are characterized by adding significant height to the superstructure, multiple sources of errors, since the coordination of multiple parts undoubtedly leads this, an unnecessarily high price, as a result of the multiple parts and multiple manufacturing steps, increased risk of bacteriological attack, due to the several corners and surfaces exposable to this, weaker screw for the attachment of the dental bridge, since no follow-up draft of said screw is possible since a structure is applied on top of said angled spacers. It also results in an increased complexity of the attachment of the superstructure to the implant. U.S. Pat. No. 6,848,908 discloses an arrangement including an angled spacer element of this kind, including a first passage and a second passage. The first passage is operative to fasten said spacer element in an implant, and the second passage is operative to fasten a superstructure on said spacer element. Superstructures attached to an implant without using a screw member results in less strength, difficulties in detachment and also incompatibility problems with commercially available implant systems of today.
Furthermore, U.S. Pat. No. 5,947,733 discloses a spacer element with a non-linear bore, connecting a first mouth, intended to be connected to a dental implant, and a second mouth, intended to be connected to a dental superstructure through a screw member engaging with the threaded part (132, 232, 332) of the spacer element. Thus, also this system is in need of spacer elements at least for solving the problem of guiding the mouth of a screw channel, such that it is not visible from outside the mouth of the patient.
There is therefore a need, among others, for a method of attaching or detaching a dental superstructure to a dental implant at a chosen angle without adding additional height to the chosen superstructure.
Thus, there is a need for a new superstructure that may be fastened to an implant without angled spacer elements or superstructures attached to the implant with only adhesive or with other techniques not based on the use of a screw member. There is also need for a simpler, faster and cheaper production method of dental superstructures, while still providing the benefits according to above. Furthermore, there is a need to provide for the possibility of a simple assembly ex situ (outside the patient's mouth) and application in situ (in the patient's mouth).
Hence, an improved superstructure, and a manufacturing method thereof, would be advantageous, and in particular a superstructure, and a manufacturing method thereof, allowing for the exclusion of angled spacer elements or fastening of a superstructure to an implant by adhesives, without being forced to place the mouth of the screw channel on a visual surface of the dental superstructure would be advantageous.